There are three presentations of attention-deficit hyperactivity disorder (ADHD) recognised in the Diagnostic and Statistical Manual of Mental Disorders – 5th edition (DSM-5TM):1

Predominantly inattentive

Predominantly hyperactive-impulsive

Combined inattentive-hyperactive-impulsive.

Rates of ADHD presentations vary across studies.2-5 A worldwide meta-analysis of 86 studies in children and adolescents and 11 studies in adults indicated that the predominantly inattentive type of ADHD was the most common subtype in all samples, with the exception of pre-school children, in whom predominantly hyperactive-impulsive type was the most common (Figure).2*

The prevalence of ADHD presentations changes with patient age, according to preliminary evidence from a cross-sectional meta-analysis of 97 studies (n=175,800). Reproduced with kind permission.2

Other investigations have reported different ADHD presentation prevalence in children and adolescents:

A study of 413 clinically referred children and adolescents with ADHD reported that 61% of participants were combined type, 30% were inattentive type and 9% were hyperactive-impulsive type.3

A US study recruited 107 clinically referred adult outpatients (aged 18–55 years) with ADHD and used structured interviews to determine ADHD presentation. Results indicated that 62% of the adults were combined type, 31% were inattentive type and 7% were hyperactive-impulsive type ADHD.5

Data obtained from clinically referred patients typically include a higher proportion of combined inattentive-hyperactive-impulsive individuals. It has been proposed that people meeting criteria for combined type ADHD may be more likely to be referred for clinical services.2

*These studies were conducted prior to publication of the Diagnostic and Statistical Manual of Mental Disorders – 5th Edition (DSM-5TM)